Various types of methods and apparatus for externally testing tubular members have been heretofore provided, such as the methods and apparatus shown in U.S. Pat. Nos. 3,921,437; 3,371,521; 3,478,577; 3,358,497; 3,034,339; 2,587,192 and 2,761,311. In those devices which are split to wrap around the tubular members to perform an external test, the structure and arrangement of such external testers is bulky and valuable time may be lost in positioning the device about the pipe and the connection to perform the test and thereafter removing the device from the pipe so that the tubular members may be moved relative to the tester. This is particularly true where the device is employed in running tubulars such as production tubing, surface pipe or casing in an oil or gas well. In some instances, it is desirable to complete the test as quickly as possible and with a minimum of time lost in maintaining the pipe stationary to inhibit sticking of the pipe, or to inhibit other problems that may be encountered to those skilled in the art. In those devices heretofore contemplated for permanent positioning about tubular members during external testing thereof, the longitudinal extent of the devices and the manner in which the seals are actuated not only may render them difficult for use in that the position of the tongs relative to such longer bodies makes it awkward and difficult for the tongs to be readily manipulated by the tong operator but the volume of fluid externally of the connection may reduce the sensitivity and accuracy of the test. Such devices also do not necessarily provide a satisfactory construction for performing an external test on tubular members, particularly where the test is performed as the tubular members are being run into an oil or gas well, so as to form the seals externally about the connection, perform the test and then release the seals so that the pipe may be moved therethrough with a minimum of time lost and a minimum of effort. Such devices also have not necessarily provided the desired ability to seal completely and effectively in repetitive operations and to hold such seals under high pressures.
The present invention is directed to a method and structural arrangement of an external tester which may be maintained and positioned about the pipe when it is being run in or removed from an oil, gas or other type well to enable a seal to be formed around a connection to seal the connection off and externally test it for leaks, and thereafter disengage the seal from the tubular member to permit the tubular member to be moved longitudinally through the test unit and into or out of the well bore.
A further object of the present invention is to provide an external tester for testing connections between tubular members including a body having an opening extending longitudinally therethrough, such body having longitudinally spaced annular seal means therein with passage means in the body for conducting fluid to move the seal means radially away from the body and into the opening to seal about the tubular members and isolate the tubular member connection in a chamber between the seal means and additional fluid passage means for conducting fluid to the chamber between the seal members to externally test the connection between the tubular members for leaks.
A further object is to apply fluid pressure directly against annular seals to move them radially into sealing engagement with tubular members to seal off a connection between the tubular members even though the tubular members may be out-of-round, or may be slightly oversize or undersize relative to the standard normal diameter of the tubular members.
A further object of the present invention is to provide an external tester for testing connections between tubular members including a body having an opening extending longitudinally therethrough, such body having longitudinally spaced annular seal means therein with passage means in the body for conducting fluid to move the seal means radially of the body to seal about the tubular members and isolate the tubular member connection in a chamber between the seal means, the chamber being only slightly larger than the connection to form a chamber of minimum volume in the body, and additional fluid passage means for conducting fluid to the chamber between the seal members to externally test the connection between the tubular members for leaks. Additional annular seal means are carried by the body between the spaced seal means with passage means for conducting fluid pressure to move the additional seal means radially of the body and into the opening to seal against the connection and isolate one end of the connection from the other end with additional passage means in the body for communicating with the isolated ends of the connection for selectively externally testing the ends of the connection for leaks.
Still another object of the invention is to provide an external leak tester for tubular members which are connected by a connection including a body having an opening extending longitudinally therethrough for receiving the tubular members and connection therein, therebeing spacer means mounted in the body opening forming annular recesses spaced longitudinally within the body opening and annular seal means mounted in the recesses. Fluid passage means are provided in the body for communicating with the seal means to urge them into sealing engagement in the recesses and simultaneously radially of the body opening for sealably engaging the connection on the tubular members therebetween. The seal means comprises an annular elastomer body having surfaces extending toward the tubular members and back-up means on the surfaces for aiding in inhibiting extrusion of the elastomer when it is urged radially of the body opening to sealingly engage the tubular members.
Another object of the invention is to provide a method for externally testing a connection between tubular members by positioning the connection between spaced annular seal means and applying fluid pressure to the seal means to move the spaced seal means radially to seal off the connection and form a chamber between the seal means. Fluid is injected into the chamber to a pressure significantly greater than the internal pressure in the connection and any fluid inflow is instrumentally noted. The connection may be tested by initially making it up to engage an internal seal without engaging an external connection seal. Thereafter, the seal means are released and the connection is made up to full recommended torque and again tested. If the connection is leak proof, the seals are retracted and the tubular members may be lowered through the test until into the well bore. If the test is initially conducted with the connection fully made up, the seals are retracted and the tubular members are run into the well bore, if the connection is leak free. If it leaks, the leak may be repaired, or the tubular members disconnected and replaced. In some instances the external test is conducted only after the initial seal has been established, and if it does not leak, the connection is released from between the seals, the connection fully made up and run into the well.
Another object of this invention is to provide an improved method and apparatus for externally testing tubular members in which longitudinally spaced annular seals may be moved radially inwardly and outwardly repetitively responsive to the supplying and withdrawing of a pressurized actuating fluid against the outer circumferential surface of such seals to form a closed chamber around the exterior of the tubular members between the seals of the body and such seals will, even after repetitive operation, completely and effectively form a sealing relationship against the tubular member which will repetitively withstand the high pressure differentials across the seals.
Other objects and advantages of the invention will become apparent from a consideration of the description and drawings.